Internal-combustion engine of the fuel-injection type



NM. 2 1926, L605,@

H. SCHNEIDER INTERNAL GOMBUSTION ENGLNE OF THE FUEL INJECTION TYPE Filed Feb; 5. 1924 HEINRICH SCHNEIDER, OF WINTERTHUR, SWITZERLAND.

INTERNAL-COMBUSTION ENGINE OF THE FUEL-INJECTIUN TYPE.

Application filed February 5, 1924, Serial No.

The present invention relates to internal combustion engines with which the fuel 1s injected withoutthe aid of compressed air and which are provided with a projecting 5 part or a displacer on. the piston head whereby at the end of the compression stroke a whirl is produced by the projection part on the piston head entering into a con.- stricted portion of the cylinder, an annular clearance being present between the con stricted portion and the displacer.

According to the present invention that annular clearance, in contradistinction to the hitherto known constructions 'of these engines, is essentially reduced to such a degree that a proper working of the piston 1s just possible, and a few enlarged portions or channels are provided in this annular gclearance, through which channels strong compact jets of air are produced when the air is displaced towards the end of the compression stroke, the fuel jets being injected into said air jets.

With known engines of this type the Width of he annular clearance is not reduced-to a minimum amount but it is chosen substantially larger in order to provide for a -sufficiently large passage area for-the displaced air. Thereby a current of air is generated having an annular cross-section and a uniform strength all round, which current is not suitable for atomizing single fuel jets.

Instead of this known current or et of air in the .shapeof a hollow cylinder or 1101.

low cone through which the injected fuel jets pass very easily a strong, compact et of air is necessary which completely ato mizes the fuel jet injected into it and WhlCh distributes as uniformly as possible the atomized fuel throughout in the combustion space.

One or more such compact air ets aregenerated according to the present inven-- tion by providing one or more enlargements of the passage areas between the displacer and the constricted part of the cylinder, which enlargements give the necessary shape to the air jet, the remaining annular clearance being kept as narrow as possible. In this way thetotal quantity of the displaced air is almost completely utilized for atomizing the single fuel jets, only an insignificant quantity of air which is lost for 5 atomizing purposes passes through the annular clearance wherein it is intensely 690,774, and in Germany February 12, 1923.

throttled. The enlargements in the passage area cause a much smaller throttling of the effective-air jet than it is the case with the hitherto annular passage areas of uniform width and the heat losses at the walls are also essentially reduced.

The number of the enlargments and the shape and direction imparted thereby to the fuel jets can be so chosen that with any size of an internal combustion engine a complete atomizing and combustionof the fuel is attained.

By means of the compact air jets the fuel may be so distributed and burnt that scarce- 1y any traces of the fuel get into contact with the walls of the combustion space or of the displacer so that an excessive heating up and destruction of these walls, which is caused by the fuel thrown against and adhering to said walls, are prevented.

Furthermore the reduction of the width of the annular clearance in combination with the arrangement of the enlargements of the passage areapresents the advantage that the designer has .much more libertyto choose the diameter of the displacer relatively to the diameter of the cylinder as the air jets can be suitably directed and are no longer dependent on the cylinder or cone shape. The present invention is of particular importance with two stroke cycle engines having an inlet valve for the scavenging air arranged in the combustion chamber as the known arrangements and dimensions of the displace! cause the scavenging air on its way from the combustion space to the cylinder to be too much throttled.

Various constructional examples of the subject matter of the present invention are illustrated on the accompanying drawings, in which Fig. 1 shows in a diagrammatic manner a vertical section through the cylinder head of an internal combustion engine with the piston in its upper extreme position,

Fig. '2 is a horizontal section along line der having a constricted portion 2 into which the displacer 3 of the piston 3 enters. 5 denotes the narrow angular clearance between the displacer 3 and the constricted portion 2 and 4 are the enlarged passage areas or channels provided in the displacer 3 The cross-sectional area of these channels is of the same dimension as the cross-sectional area of the annular clearance with known engines. The enlarged passage areas may also be obtained by providing grooves or channels in the Wall of the constricted portion as indicated in chaindotted lines at 4*.

In the constructional example illustrated ranged in the cylinder head 18. The piston- 3 is provided with the displacer 3 entering into the combustion space 2, on the displacer three channels or grooves 4 equally spaced around the circumference are provided for theformation of the air jets when the displacer enters into the combustion space towards the end of the compression stroke. A fuel nozzle 8 is centrally arranged and pro-vided with apertures so that a jet 9' of fuel is injected into each of the three air jets 10. 11 denotes a cylindrical inlet valve for the scavenging air, the latter being supplied to the cylinder from the annular chamber 12 through the ports 13 controlled by the valve 11, the latter is actuated by means of a stirrup 1%, bell crank lever 19 provided with rollers 20 and 21, cooperating with cams 22 and 23 arranged on the known regulating shaft 24. 25 denotes the exhaust ports arranged in the lower part of the cylinder and uncovered towards the end of the expansion stroke.

The constructional example illustrated in Figs. 5 and 6' differs from that shown in Figs. 3 and 4 inasmuch as instead of one centrally arranged fuel nozzle delivering three jets of fuel three 'laterally arranged fuel nozzles 8 8 8 are provided each delivering one jet of fuel injected into the respective air jet. The injected fuel is well atomized and uniformly distributed in the combustion space so that a complete combustion is ensured.

The constructional example illustrated in Figs. 7 and 8 shows the part arranged according to the present invention in a four stroke cycle engine. The displacer 3 of the piston 3 is provided with two flattened portions 4 arranged diametrically opposite each other and the annular clearance 5 between displacer 3 and the constricted portion 2 connecting the cylinder 1 with the combustion space 26 is narrowed to a minimum amount. Into the combustion space 26 a centrally arranged nozzle 8 injects two jets of fuel 9 into said two air jets. The plane in which the centre lines of the portions 4 are situated stands at right angles to the plane through, the axes of the controlling valves 27, 28.

I claim:

In an internal combustion engine of nozzle having a plurality of apertures adapted to inject at least one jet of fuel into every air jet produced the volume of each air jet being sufficient to completely atomize eachfuel jet.

In testimony whereof I aflix my signature.

HEINRICH SCHNEIDER. 

